diff --git a/src/Shared/HandyControl_Shared/Controls/Input/CheckComboBox/CheckComboBox.cs b/src/Shared/HandyControl_Shared/Controls/Input/CheckComboBox/CheckComboBox.cs
index 8d2b5b99..cf626bda 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/CheckComboBox/CheckComboBox.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/CheckComboBox/CheckComboBox.cs
@@ -196,7 +196,7 @@ namespace HandyControl.Controls
                 isError = Validation.GetHasError(this);
                 if (isError)
                 {
-                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent);
+                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent?.ToString());
                 }
                 else
                 {
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/ComboBox.cs b/src/Shared/HandyControl_Shared/Controls/Input/ComboBox.cs
index d178848c..94c838ef 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/ComboBox.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/ComboBox.cs
@@ -368,7 +368,7 @@ namespace HandyControl.Controls
                 isError = Validation.GetHasError(this);
                 if (isError)
                 {
-                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent);
+                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent?.ToString());
                 }
                 else
                 {
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/DatePicker.cs b/src/Shared/HandyControl_Shared/Controls/Input/DatePicker.cs
index 66fe911e..515d62d9 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/DatePicker.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/DatePicker.cs
@@ -164,7 +164,7 @@ namespace HandyControl.Controls
                 isError = Validation.GetHasError(this);
                 if (isError)
                 {
-                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent);
+                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent?.ToString());
                 }
                 else
                 {
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/DateTimePicker.cs b/src/Shared/HandyControl_Shared/Controls/Input/DateTimePicker.cs
index db1543c3..b694bbb7 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/DateTimePicker.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/DateTimePicker.cs
@@ -447,7 +447,7 @@ namespace HandyControl.Controls
                 isError = Validation.GetHasError(this);
                 if (isError)
                 {
-                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent);
+                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent?.ToString());
                 }
                 else
                 {
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/NumericUpDown.cs b/src/Shared/HandyControl_Shared/Controls/Input/NumericUpDown.cs
index ab2247d8..a1d20927 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/NumericUpDown.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/NumericUpDown.cs
@@ -128,7 +128,7 @@ namespace HandyControl.Controls
 
                 if (Validation.GetHasError(this))
                 {
-                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent);
+                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent?.ToString());
                     SetCurrentValue(IsErrorProperty, ValueBoxes.TrueBox);
                 }
             }
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/PasswordBox.cs b/src/Shared/HandyControl_Shared/Controls/Input/PasswordBox.cs
index 49e0d64d..7f85902c 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/PasswordBox.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/PasswordBox.cs
@@ -269,7 +269,7 @@ namespace HandyControl.Controls
                 isError = Validation.GetHasError(this);
                 if (isError)
                 {
-                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent);
+                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent?.ToString());
                 }
                 else
                 {
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/TextBox.cs b/src/Shared/HandyControl_Shared/Controls/Input/TextBox.cs
index 6cf338eb..ba7a2e9a 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/TextBox.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/TextBox.cs
@@ -123,7 +123,7 @@ namespace HandyControl.Controls
                 isError = Validation.GetHasError(this);
                 if (isError)
                 {
-                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent);
+                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent?.ToString());
                 }
                 else
                 {
diff --git a/src/Shared/HandyControl_Shared/Controls/Input/TimePicker.cs b/src/Shared/HandyControl_Shared/Controls/Input/TimePicker.cs
index 2a39fe1d..921f7f54 100644
--- a/src/Shared/HandyControl_Shared/Controls/Input/TimePicker.cs
+++ b/src/Shared/HandyControl_Shared/Controls/Input/TimePicker.cs
@@ -406,7 +406,7 @@ namespace HandyControl.Controls
                 isError = Validation.GetHasError(this);
                 if (isError)
                 {
-                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent);
+                    SetCurrentValue(ErrorStrProperty, Validation.GetErrors(this)[0].ErrorContent?.ToString());
                 }
                 else
                 {